Python CPython up to 3.11.8/3.12.2/3.13.0a4 Address Header information disclosure

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Python CPython up to 3.11.8/3.12.2/3.13.0a4. The impacted element is an unknown function of the component Address Header Handler. The manipulation leads to information disclosure. This vulnerability is traded as CVE-2025-1795. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Python CPython up to 3.11.8/3.12.2/3.13.0a4. This issue affects an unknown functionality of the component Address Header Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

During an address list folding when a separating comma ends up on a folded line and that line is to be unicode-encoded then the separator itself is also unicode-encoded. Expected behavior is that the separating comma remains a plan comma. This can result in the address header being misinterpreted by some mail servers.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2025-1795 since 02/28/2025. The exploitation is known to be difficult. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 232012 (Linux Distros Unpatched Vulnerability : CVE-2025-1795), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.11.9, 3.12.3 or 3.13.0a5 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (232012), EUVD (EUVD-2025-5930) and CERT Bund (WID-SEC-2025-1850). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Xerox FreeFlow Print Server

Productinfo

Type

• Programming Language Software

Vendor

• Python

Name

• CPython

Version

• 3.11.0
• 3.11.1
• 3.11.2
• 3.11.3
• 3.11.4
• 3.11.5
• 3.11.6
• 3.11.7
• 3.11.8
• 3.12.0
• 3.12.1
• 3.12.2
• 3.13.0a4

License

• open-source

Website

• Product: https://github.com/python/cpython/

CPE 2.3info

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CPE 2.2info

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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